Oracle pl/sql Change Array Size and Members After Delete - sql

Question

For example i have an array like
"a(1):=1 ,a(2):=2, a(3) := 3"
and now my array count =3 "(a.count)"
then i delete middle member "a.delete(2)" then i wanna make my array like this "a(1):=1;a(2):=3" and my array count = 2 ("a.count") how can i do this ?
ps:i need to this with big sized array so i think i should use, for or while loop but how...

Answer 1

The collection where you have deleted some element is called sparse collection. Below you have example how to iterate that type of collection and how to use it with forall.
declare
type a is table of number;
ar a;
v_idx number;
begin
select level bulk collect into ar from dual connect by level< 1000;
ar.delete(1);
ar.delete(4);
ar.delete(10);
ar.delete(88);
v_idx := ar.first;
while v_idx is not null loop
dbms_output.put_line('idx: '||v_idx ||' value:'|| ar(v_idx));
v_idx := ar.next(v_idx);
end loop;
-- FORALL i IN INDICES OF ar
-- INSERT INTO test_table VALUES ar(i);
end;

Answer 2

Thank you but i should change array too , i need to take same output when i print array members like
for i in ar.first..ar.last loop
dbms_output.put_line(ar(i));
end loop;

Answer 3

declare
type a is table of number;
ar a;
begin
select level bulk collect into ar from dual connect by level< 1000;
ar.delete(1);
ar.delete(4);
ar.delete(10);
ar.delete(88);
-- ar is sparse collection;
ar := ar MULTISET intersect ar;
-- ar is dense collection and for i in .... is possible
FOR i IN ar.first .. ar.last LOOP
DBMS_OUTPUT.put_line(ar(i));
END LOOP;
end;

Answer 4

you can try this approach assign values of first spared collection to second continues collection and use second collection for further processing...
declare
type num_arr is table of number;
v_num_arr1 num_arr; --first collection
v_num_arr2 num_arr := num_arr(); -- second collection initialization and declaration
v_idx number;
v_col_index number := 1;
begin
-- fill 10 element.
select level || '1' as num1 bulk collect into v_num_arr1 from dual connect by level < 10;
for x in v_num_arr1.first .. v_num_arr1.last loop
dbms_output.put_line('index: ' || x || ' value: ' || v_num_arr1(x));
end loop;
dbms_output.put_line('');
-- delete element
v_num_arr1.delete(3);
v_num_arr1.delete(7);
v_idx := v_num_arr1.first;
while v_idx is not null loop
dbms_output.put_line('index: ' || v_idx || ' value: ' || v_num_arr1(v_idx));
-- filling second collection with regular index by variable v_col_index
if v_num_arr1(v_idx) is not null then
v_num_arr2.extend(1);
v_num_arr2(v_col_index) := v_num_arr1(v_idx);
v_col_index := v_col_index + 1;
end if;
v_idx := v_num_arr1.next(v_idx);
end loop;
dbms_output.put_line('second collection elements
');
--check second colleciton
for x in v_num_arr2.first .. v_num_arr2.last loop
dbms_output.put_line('index: ' || x || ' value: ' || v_num_arr2(x));
end loop;
end;